Re: [PATCH] usb: gadget: f_fs: increase eps_revmap length

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, Sep 12, 2023 at 06:34:17PM +0800, Jiazi.Li wrote:
> Commit 41dc9ac163e7 ("usb: gadget: f_fs: Accept up to 30 endpoints.")
> increase eps_addrmap length to 31, eps_revmap also need to increase.
> Increase it's length to 32.

Why 32?

> 
> For same-address, opposite-direction endpoints, will use same idx in
> eps_revmap, so add new marco REVMAP_IDX to calculate idx for endpoints.
> 
> Signed-off-by: Jiazi.Li <jiazi.li@transsion.com>

Please use your real name here, not your email alias.  Same for the
 From: line in your email


> ---
>  drivers/usb/gadget/function/f_fs.c | 9 +++++----
>  1 file changed, 5 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index 6e9ef35a43a7..4a210368bd33 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -71,12 +71,14 @@ struct ffs_function {
>  	struct ffs_data			*ffs;
>  
>  	struct ffs_ep			*eps;
> -	u8				eps_revmap[16];
> +	u8				eps_revmap[32];
>  	short				*interfaces_nums;
>  
>  	struct usb_function		function;
>  };
>  
> +#define REVMAP_IDX(epaddr)	((epaddr & USB_ENDPOINT_NUMBER_MASK) \
> +				* 2 + ((epaddr & USB_DIR_IN) ? 1 : 0))

What is the * 2 for?  Also, this macro is hard to read, can you make
this an inline function instead, explaining what you are trying to
calculate?

thanks,

greg k-h